Process for the manufacture of metallic sodium.



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To all whom it 6 Rue Felix Poulat, Grenoble, Tserc,Repubpnrrnn srn rnsrgrnnr orricn TO SOCIETE DELECTRO-CHIMIE, OF GRENOBLE, FRANCE.

PAUL LEON HULIN, OF GRENOBLE, FRANCE, ASSIGNOR QF PARIS, FRANCE, ANDPAUL LEON HULIN,

PROCESS FOR THE MANUFACTURE OF METALLIC SODIUM.

Specification of Letters Patent.

971,198. Patented Sept. 2%, 1916.

No Drawing. Original application filed October 27, 1908, Serial No.459,728. Divided and this application filed June 2, 1909. Serial No.499,737.

then'to replace it in position. Such water or solution constitutes arestorative liquid. By this process the working remains regular, thedecrease in the production is arrested and the inconvenience, due to thefrequent replacement of the caustic soda and to the dismounting of thewhole apparatus, is entirely removed.

It should be noted-that in the present case there is not visiblemanifestation of dirt deposition on the cathode and that the new mayconcern: Be it known that I, PAUL Liion HULIN, of

lie ,of France, engineer, have 'invented a Process for the M anufactureof Metallic Soof which the following is a full, clear,

l and exact description, this being a division of my application forLetters Patent fori means for the electrolytic manufacture of sodium,Serial No. 459,728, filed. October 27, 1908.

It has been noticed in the manufacture of sodium, by means of theelectrolysis of fixed 5 caustic soda, that during the carrying out of ltrolytic cases where incrustations are formed on the electrodes. Itshould also be re the process, the quantity of sodium produced nml'kedthat, on contrary: ceftam decreases somewhat after a short time. ,Thiselectl'Olytlc Qperatlons and PfiTt1C1lla11y 1n phenomenon cannot beattributed to an inthe P p? of Chloratesfl the fonlmtlon crease i th ita f th b h or to of deposits on the cathode is considered as favorableto the ellicient working of the operation.

Claims:

1. The herein described process for the manufacture of metallic sodium,which consists in subjecting fused caustic soda to electrolysis,withdrawing the cathode periodically, bringing it into contact with arestorative liquid, and then replacing it for continuing theelectrolytic operation.

2. The herein described process for the manufacture of metallic sodium,which consists in subjecting fused the surface of the electrodes. Uptill now it 1 has been surmised that the decrease in the production wasdue to impurities in the caustic soda, silicic acid, iron oxid, etc., lwhich are contained even in the purest soda, I the proportion of theimpurities increasing as the decomposition of the sodais carried out.This supposition was apparently confirmed by the fact that the quantityof sodium produced decreased all the more rapidly when the soda was veryimpure. nder these COIldltlOIlStllQ disadvantage could only be remediedby taking the electrolytic vat out of circuit. to dismount and clean it,as soon as its eiliciency began to decrease, then refilling it with newcaustic soda and putting it to work again. It is easy to imagine theloss of time and the considerable l labor necessitated by such aprocess; more- 1 over, to obviate the too frequent dismountl ing, andclcansin ODQlRtlOllS,OlllY soda of the. purest grade was used which veryexpen- 1 sive, and had to be rejected when it had only supplied a smallquantity of sodium. The new process does away with these disadvan- Itages and enables sodium to be produced in l l l l I l trolysis,withdraw'ng the cathode periodically, bringing it into contact withwater to restore its efficiency, and then replacing; it for continuingthe electrolytic operation.

3. The herein described process for the manufacture of metallic sodium,which con sists in subjecting fused caustic soda to electrolysis,withdrawing the cathode when its eiliciency becomes materiallydiminished, and continuing with a cathode of greater ellicicncy.

The TOTQQ'Olllg specification of my process for the manufacture ofmetallic sodium a practical manner and under economical signed by methis seventeenth day of May conditions by electrolytic means. 1.909. r TThe principle of the process consists in in- UL EON HUlilh.

Witnesses:

termittently. taking the cathode out of the bath, in bringing it intocontact with water or with any solution of aqueous nature and DEAN B.hlAsoN, 1t. l lnnuor.

process cannot be compared to other electhe electrolytic operationcaustic soda to elec-

